Various types of batteries have been developed heretofore, and in every battery, a packaging material is an essential member for sealing battery elements such as an electrode and an electrolyte. Metallic packaging materials have often been used heretofore as battery packaging materials, but in recent years, batteries have been required to be diversified in shape and to be thinned and lightened with improvement of performance of electric cars, hybrid electric cars, personal computers, cameras, mobile phones and so on. However, metallic battery packaging materials that have often been heretofore used have the disadvantage that it is difficult to keep up with diversification in shape, and there is a limit on weight reduction.
Thus, in recent years, a film-shaped laminate including a base material layer, an adhesive layer, a barrier layer and a sealant layer laminated in this order has been proposed as a battery packaging material which is easily processed into diverse shapes and which can be thinned and lightened (see, for example, Patent Document 1). The film-shaped battery packaging material is formed in such a manner that a battery element can be sealed by heat-welding the peripheral edge by heat sealing with the sealant layers facing each other.
On the other hand, in a conventional film-shaped battery packaging material, usually a base material layer and a barrier layer are bonded to each other by a dry lamination method with a two-pack type curable adhesive to laminate the base material layer, an adhesive layer and the barrier layer, and for curing the adhesive layer, it is necessary to perform aging under a high-temperature condition for several days to several weeks. Accordingly, the conventional film-shaped battery packaging material has the disadvantage that a step of curing an adhesive layer causes an increase in lead time, leading to occurrence of product defects due to exposure to a high-temperature condition and a temperature change for a long period of time.
Thus, it is earnestly desired to develop a technique which is capable of quickly curing an adhesive layer provided between a base material layer and a barrier layer in a film-shape battery packaging material, so that the lead time can be reduced, leading to improvement of production efficiency.